Here is a puzzle for calculator or spreadsheet practice.

Tom, Dick and Harry are brothers. At 11 am all brothers are at home. At 11 am Tom starts to walk at 4 miles per hour north to a distant destination. At 11:05 Dick starts to walk south to another distant destination. Dick walks at a constant 3 miles per hour. At 11.30 Harry, who is still at home, discovers that both his brothers have forgotten their packed lunches so he sets off north on his bicycle at 9 miles per hour to catch up with Tom to deliver his lunch. He then immediately doubles back to catch up with Dick, going past his home without stopping. Having caught up with Dick and delivered his packed lunch, Harry cycles back home, again at a constant 9 miles per hour. What time does he arrive home, having completed both deliveries? And would he be earlier or later if he had chased after Dick first and Tom second?

Correct answers were received from Clem Robertson, Rosemary West, John Stafford and John Bownas. Rosemary West won the draw and the book token.

THE ANSWER -- scroll down to it...




















The answer is 1.31 pm and it would have been quicker to have chased after Dick first.

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